Bituminous concrete revetment



Feb; 12; 1935.

Filed Feb.

4A. c. DEER BITUMINOUS CCNCRETE REVETHENT 2 Sheets-Sheet l` QALZDger L M f7 f Feb. 12, .19355,

Aci. .DEER

. -B-ITUMI`NOUS CONCRETE REVETMENT Filed Feb. 5,.'1932 2 SneeisL-sneet 2 'a 24j 524 2f mvem'o AT1-dann',

Patented Feb. 12, 1935 I UNTED STATES lPlsfrrzlw'r OFFICE 6 Claims.

One distinctive feature of my invention relates to the method of production and laying of such a slab, and according to this feature of my invention I propose to manufacture the slab on a barge as a long continuous strip anchored along its shore end and laid as produced to form a continuous revetment strip extending across the width and length of the zone to be protected. As the revetment is thus produced and laid in position the barge or barges carrying the production equipment is shifted to facilitate laying of the revetment. t

The distinctively novel feature of this revetment method lies in the fact that continuous slab 1 strips can be laid at right angles to the axis of the stream or otherwise in a simple'and convenient manner to insure proper coverage of the bed and bank area. 'I'he revetment can be` allowed to settle into position on the river bed without necessitating the diicult task, of placing in position under Water independent rigid slabs and anchoring them over an irregular bed as has heretofore been the practice with permanent slab revetment work. f Y

A further feature of my invention, which is essential to the practice of the method of-laying above described, consists in the production of a exible revetment slab or strip from materials that are resistant to water and can be introduced while hot into water without disintegration or the productionof leakage cracks therethrough.

A further distinctive feature consists in the production of these revetment slabs or strips of such a composition that they will have exibility suilicient to enable them to conform tothe contour "of the bank or stream bed upon which they larlty in the same." T o thisfend, and in order to prevent cracking of the slab or mat responsive .to sharp bends up or down or laterally in any direction, 4my invention contemplates reinforcing the slab not onlyby suitable embedded metallic are to be laid, regardless of any ordinary irregu-l reinforcement but also applying to either or both of its top and bottom surfaces a layer of fabric, water-proof paper or other flexible material having substantial inherent strength and which will reinforce such surfaceand prevent the formation 5 of surface cracks in the slab or strip as it gradually adjusts itself to the contours of its foundation or base. support. I

The practice of my improved method for preparing and laying revetment slabs or strips will l0 better be understood by reference to the accompanying drawings in which I have sought formally to illustrate a typical apparatus for producing and laying these slabs,` and in 'Whichz- Fig. 1 shows in side elevation a barge carrying slab production equipment engaged in the manufacture of a slab which is being laid as it is produced.

.In Fig. 2 I show a section of revetment that is being laid with the slab strips in overlapped position, the barge being broken away.

Fig. 3 is an enlarged plan view of one end of a revetment strip broken away to show its various component layers.

Fig. 4 is a side view of Fig. 3. f

Similar reference numerals refer to similar parts throughout the drawings.

I have illustrated in Fig. A1 what I regard as a typical apparatus for the production and laying of a revetment slab or strip 9 in accordance with my present invention. This apparatuses shown, comprises a barge 10 adapted to be anchored op- -posite the bank upon which it is intended that the revetment slabs'or strips shall be laid. The barge may bef'moved by its own power or by any other means to the proper location and anchored there, suitable provision being made for gradually moving it olf shore yto theextent required for the particular work.

It is contemplated that the material for the production of bituminous concrete for the slabs will be supplied tothe barge by any suitable means such as the crane feeder 11 whchwill deliver the suitably graded aggregate 12 into a bin 13 from which it will be delivered by a -feeder 14 and elevator 15 to a dryer 16. From the dryer the material passes by an elevator 17 to a supply bin 18, from which it passes to a pug mill 19 where the bituminous bonding material is mixed with the hot aggregate and the resultant bituminous concrete is then delivered to a spreading and finishing machine 20. y

This machine 20 forms the bituminous concrete into a slab or strip of the desired width-and thickness which is laid on a bottom strip of fabric 6,5

respectively, the metallic reinforcement 24 being embedded in the slab and properly spaced from top and bottom thereof. The conveyor is of the continuous belt type mounted except at its inner end to travel on a roll conveyor frame, the belt having a driving roll 27 at its inboard end.v The motor drive for this roll 27 is omitted for the sake of clearness.

Thebituminousconcrete .passes under a top finishing roll" 28 to level and smooth its top surface 'and to properly compress it. A second reel 29 may be .provided above the conveyor belt and a second compression and finishing roll 30 disposed beyond this reel, thus permitting a top layer 31 of fabric or paper reinforcement to be applied to bituminous concrete body 32 of the slab.

The slab thus continuously produced and while still hot is fed forward on the conveyor belt to the outboard end 33 of the conveyor frame which is hinged at 34 to the level conveyor frame on the barge. By a suitable rigging 35 the outboard end of the conveyor can be swung up or down like a boom according to the delivery position desired for the slab or strip. Itis shown' raised sharply so that the outboard end of the strip 9 can be suitably anchored.` I hinge at the outboard end of the conveyor boom an apron 36 over which the slab is discharged onto the bank or river bed 37 as produced. Q

As a part of the metallic wire mesh reinforcement of the slab I run lengthwise thereof.` heavy wires 38. I anchor the outboard end of the slab or mat by anchor posts 39 driven through holes strip will overlap of the river bed which is revetment slabs 1- and bed'wiu have formed therefor near the end of posts being placed on the bank at the high level for the revetment work. These anchors :are so placed that the down stream side edge of each the up stream edge of the adjacent previously laid slab as is shown in Fig. 2, thus giving a complete revetrnent strip covering for the exposed shore line and for that portion to be protected by the revetment. Should it be desired vto anchor the submerged end of the revetment slabs this may be done in any practical way.

The methodof forming and laying these revetment slabs thus provides the bank with continuous revetment strips each running continuously from the bank over the portion of the stream bed to be protected and therefore a minimum opportunity exists for leakage or disarrangement.

With the slabs arranged to overlap as described,

I provide a continuous and complete permanent coverage for the protection of the banks and bed of the stream.

vIt is essential for the successful use of such that theyl shall be of such a natureas to readily adjust themselves to any normal surface irregularity in bank or stream bed. It is of course contemplated that the bank even surface because the slabs made in accordance with my invention the strip, the v had the stumps and large stones removed but it is unnecessary that they be graded to a smooth or '15 are capable of bending about a 180 degree arc having as low as a ve foot radius. i

Having started the manufacture of a slab the production is continuous. 'I'he conveyor boom is rst set and the barge shifted so that the free end of the slab can be delivered to the bank and anchored in position on the shore. Thereafter, as the production of the slab proceeds the hoisting tackle supporting the conveyor boom is eased so that the latter follows down bank and stream bed, this movement being coordinated with the shifting of the barge outwardly, at right angles to the bank, and the two adjustments continue until the requisite length of revetment slab or strip has been produced, whereupon it is cut off and is fed outwardly until it is laid with its other end anchored, if desired in position on the stream bed. l

Having completed one slab the barge is shifted up stream and the process is resumed to produce the next strip. The whole process is thus ccntinuous, and it is possible to produce slabs of substantial width, running from `6 to 15 feet, having any desired length up to several hundred feet and being of the requisite thickness. The metallic reinforcement employed can be designed in accorda-nde with established engineering practice, the same with the increase in thickness of the slabs.

`In order to provide the requisite flexibility in the bituminous concrete slab and to adapt it to bend under water without cracking, I prefer to use the following composition, but do not intendto limit myself thereto. -I blend coal tar and pitch -in proportions to produce a bituminous composition having a melting point of between 100 and 150c F. To from 25 to 50 parts of this bituminous material I add from 50 to 75 parts of calcium carbonate nely ground and onefourth to one part of aluminum potassium sulfate all thoroughly mixed to form the bituminous bond.

To each part of the bond produced I add by weight from three to six parts of properly graded aggregate, and the bituminous concrete is formed by thoroughly mixing these constituents in a pug mill before spreading it into the slabs or strips. f

The top and/or bottom layer of cloth, suitable.

paper, fine mesh wire cloth, or combinations of the same, will add to the strength and reinforcement of the slab, particularly as it is being produced and will facilitate in being delivered to its bed, such delivery requiring the slab to follow convex or concave curves in being delivered and to freely accommodate itself to its bed. This surface reinforcement is essential to prevent fine cracks starting up about the convex surface lof the bends where the surface material comes under tension stresses. The bottom layer of fabric or the like is essential for the continuousmanufacture and transportation of the bituminous being increased proportionately concrete slab to its bed, since the material, where .n inforcing layer.

'Ihe necessity for the top layer will depend upon whether the top surface will be subjected to tension liable to crack same, in which event the top surface should also have a reinforcement layer. It is of course understood that this reinforcing 4layer will perhaps rapidly disintegrate after the slab is laid and it is not looked to for ature without becoming rigid.

'. claims.

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of vvarious changes and modifications, without d eparting from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or as are specifically set forth in the appended 1. A revetment strip of unitary construction comprising a exible strip formed of a permanent and inherently resilient bituminous mixture having reinforcing members embedded therein, 'the mixture consisting of a'v bond composed of bitiminous materials having a low melting point combined with finely divided calcareous -material andl amminum potassium sulfate, and a graded aggregate.

2. A revetment comprising strips of bituminous material, each of which is unitary in construe# tion and permanently and inherently resilient,

and a reinforcing layer applied to the un'der surface of said strips, the bituminous material consisting of a bond formed of tar and pitch havinga melting point of between 100,and 150 F.4

to which has been addafinnz divided chemin carbonate and aluminum potassium sulfate and a graded aggregate. v

3. A revetment comprising strips of bituminous material, eacl'lof which is unitary inconstruction and permanently and inherently resilient, a reinforcing layer applied to the under surface of said strips, and metallic reinforcing members embedded in the strips, the material comprising a graded aggregate and a bond formed Aof from 25 to 50 parts of a-tar and pitch composition having a melting point of 100 to 150 F. thoroughly mixed with from 50 to 'l5 parts of finely ground calcium carbonate, and. 'one-fourth to one part of aluminum potassium sulfate.

4. A bituminous concrete revetment comprising 'continuous overlapping strips of bituminous concrete consisting of a bond composed of biltuminous `materials having 'a low melting point bituminous concrete applied on the fabric layer finely ground calcium carbonate, and one-fourthv to one part of aluminum potassium sulfate. v -A'mEE c. DEER. 

